What Causes Brownish Discharge And Abdominal Pain After Intercourse?

hello i am unsure if my hymen has been broken or not i would appreciate it if you could answer some of my questions. My boyfriend recently inserted his penis into my vagina and it was very painfull but he could only go in so deep so we thought it wasn't broken. Could this only mean that he is too big to fit in all the way? (this was my first time having sex). The next day after this had happend i had lower abdominal pain and a very light brown discharge. This made me believe that my hymen was broken but i am unsure.